Soil tilling apparatus such as garden cultivators and plows have been used for a long time. With the wide use of small gasoline engines, such apparatus have used such engines. The prior structures have included a large drive wheel connected to the engine to be driven thereby and a frame supporting the engine from the drive wheel and the soil tilling tool.
Difficulties have been encountered with such prior apparatus as they were cumbersome and heavy to handle. Such devices have added outrigger wheels to assist in supporting the weight (H. Marcoux U.S. Pat. No. 3,168,148 and A. C. Johnson U.S. Pat. No. 2,457,821), have used two drive wheels with means for preventing one wheel from moving to assist in turning (G. E. Smithburn U.S. Pat. No. 2,824,506 and W. G. Hardy et al U.S. Pat. No. 2,626,671), have used widely spaced, separately powered drive wheels with outrigger rear wheels for weight distribution (F. V. Donald U.S. Pat. No. 1,768,673), and have placed the transmission over the drive wheel to increase traction and avoid counterbalancing (A. C. Johnson U.S. Pat. No. 2,457,821).
Such prior apparatus have not solved the turning problem to allow a soil tilling apparatus to reach substantially all of the ground in a garden plot while still providing a powerful apparatus which is easy to control and does an excellent job of soil tilling.